National Citizenship Day (Sept 17): A Perfect Prompt to Research Your Immigrant Ancestors’ Path to U.S. Citizenship

National Citizenship Day is every September 17, the United States marks Constitution Day and Citizenship Day—a time to honor the signing of the Constitution in 1787 and to reflect on what it means to be a citizen. It’s also part of Constitution Week (September 17–23). For family historians, that makes this the ideal moment to ask: Did my immigrant ancestors become U.S. citizens? If so, how—and if not, why not?

Why this date matters—brief history & inspiration

The observance we now call Constitution Day and Citizenship Day has evolved over time. It grew from the 1940 “I Am an American Day,” was renamed Citizenship Day in 1952, and later combined with Constitution Day—an observance that emphasizes civic learning and frequently features naturalization ceremonies nationwide. Use the date as a nudge to explore your family’s own naturalization stories.

Getting Started

First, look for quick clues: did they naturalize? U.S. federal censuses (1900–1940) are goldmines for immigration and naturalization hints. Look at the citizenship column:

AL = alien (not naturalized)
PA = “first papers” (filed a declaration of intention)
NA = naturalized

In 1920, enumerators were instructed to record the exact year of naturalization for those marked “NA.” These simple codes can guide you to the right court records or tell you a person likely never completed the process.

Tip: The 1900–1930 censuses also asked year of immigration; pair that with naturalization status to build a timeline for your ancestor’s journey.

The Core Records You Want—and Where to Find Them

1) Declarations & Petitions (“first” and “second” papers)

For much of U.S. history, naturalization was a two-step process: a Declaration of Intention (“first papers”) followed years later by a Petition for Naturalization (“second papers”). After approval, the court issued a certificate of citizenship/naturalization. These documents name spouses, children, arrival details, and addresses—often with rich narratives.

Ancestry®: Use Card Catalog → Immigration & Travel → Citizenship & Naturalization to search state and federal collections (e.g., S., Naturalization Records, 1840–1957 and numerous state-court sets). Filter by place and date. (Ancestry)

FamilySearch: The United States Naturalization and Citizenship wiki page links to free indexes and images by state and era. (FamilySearch)

National Archives (NARA): Many federal-court naturalizations are with NARA; some county and state-court holdings or indexes have been donated or microfilmed. (NARA)

Don’t forget offline: Before September 27, 1906, any “court of record” (municipal, county, state, or federal) could naturalize, so originals may still reside in county courthouses, state archives, or historical societies. Call ahead; many sets are not fully digitized.

2) Certificates and C-Files (1906–1956)

Beginning in 1906, the federal government standardized naturalization paperwork. Every person naturalized between Sept. 27, 1906, and Mar. 31, 1956 has a Certificate File (C-File) containing a copy of the certificate and related documents—immensely useful when the court record is hard to locate. These are held by USCIS (not NARA) and searchable via the USCIS Genealogy Program. (NARA)

3) Alien Registration (AR-2) forms, 1940–1944

During WWII, the government required most noncitizens aged 14+ to register and be fingerprinted. The resulting Form AR‑2 cards often include exact birthplaces, addresses, employer info, and more. As of May 17, 2024, all AR‑2s are now at NARA (requests filed after that date go through NARA, not USCIS). (USCIS)

4) A‑Files (Alien Files)

Starting April 1, 1944, the Immigration and Naturalization Service created consolidated Alien Files (“A‑Files”) for noncitizens, and after April 1, 1956, naturalization paperwork was filed in the A‑File too. Most A‑Files remain with USCIS, but older files (generally for those born >100 years ago) have been transferring to NARA. For people who arrived after 1944 or naturalized after 1956, an A‑File is often the single best dossier. (NARA)

If there’s no naturalization—ask why not?

Not every immigrant naturalized, and some didn’t need to. Consider these possibilities:

Racial or legal bars (pre‑1952): For many Asian immigrants, racial restrictions once made naturalization impossible. The Immigration and Nationality Act of 1952 ended those racial bars, a pivotal change that explains why some families show no naturalization before the 1950s. (US State Department – Office of the Historian)
Derivative citizenship through a parent: For much of U.S. history, minor children could derive citizenship automatically when a qualifying parent naturalized—which means there may be no individual naturalization record for the child. If your ancestor was a minor when a parent became a citizen, look instead for a Certificate of Citizenship (often obtained later) rather than a petition. (NARAtions)
Married women’s status shifted by law: Under the Expatriation Act of 1907, a U.S.-born woman who married a noncitizen often lost her U.S. citizenship; later, the Cable Act of 1922 began restoring women’s independent citizenship, and 1940 legislation allowed repatriation regardless of marital status. These twists can explain the absence (or presence) of a woman’s naturalization record. (NARA)
“First papers” expired: After 1906, a Declaration of Intention expired if the person didn’t file a petition within seven years, leading some individuals to restart—or abandon—the process. If you see multiple declarations, that’s why. (NARA)
Personal choice or practical hurdles: Language and civics expectations (formalized and standardized after 1906), fees, time away from work, or plans to return home kept some from finishing the process. Cross‑check directories, obituaries, and probate files for clues to intent and status.

A step‑by‑step plan you can do this week

Pick one immigrant ancestor. Note likely immigration years, residences, religion, and naturalization hints from family papers.
Search Ancestry’s “Citizenship & Naturalization” category for your target locality (county/state) and timeframe; then search the broader S., Naturalization Records, 1840–1957 collection. Browse by court when possible. (Ancestry)
Check the 1900–1940 censuses on Ancestry to read the AL/PA/NA codes and locate the 1920 “year of naturalization.” That year often matches the petition or certificate date. (History Hub)
If naturalized 1906–1956, request a USCIS Genealogy search for a C‑File—especially if you suspect the person moved often or you can’t find the court case. (USCIS)
If your person was in the U.S. during 1940–1944 and not yet a citizen, look for an AR‑2 via NARA; it’s superb for precise hometown data. (USCIS)
Post‑1944 arrivals or 1956+ naturalizations? Ask about an A‑File. Start with USCIS; if the person was born more than 100 years ago, also check NARA’s A‑File holdings. (USCIS)
Can’t find a petition for a child? Investigate derivative citizenship. Look for later Certificates of Citizenship or evidence in passports and post‑naturalization records.
Pre‑1906 immigrants: Contact county courts, state archives, and local historical societies—many early naturalizations are still held locally (and not all are online). (NARA)

Pro tips

Names flex. Try phonetic spellings, patronymics, and original‑language forms.

Follow the court. If the census says “NA” in 1920 and your person lived in Chicago, don’t just search “Illinois”—target the S. District Court and nearby counties.

Match the year of naturalization to city directories, draft registrations, or voter lists to narrow the court and filing window.

Document the “no.” If you conclude an ancestor never naturalized, record why (e.g., ineligible before 1952; declaration expired; chose to remain an alien). Future you—and your cousins—will thank you.

Your Citizenship Day call‑to‑action

This September 17, choose one immigrant ancestor and commit to a 30‑minute sprint:

Pull that ancestor up in the 1900–1940 censuses to read the citizenship status and (for 1920) the year.
Search Ancestry’s naturalization collections for a declaration or petition that matches.
If they naturalized 1906–1956, submit a USCIS Genealogy index search for the C‑File; if they were a noncitizen in 1940–1944, ask NARA about AR‑2s.
Not finding a petition for a child or a married woman? Consider derivative or marital‑status citizenship scenarios and adjust your search.

Then share what you discover—in your family tree notes, with relatives, or in a genealogy group. Your ancestor’s path to citizenship (or decision not to take that path) is a powerful chapter of your American story.

Sources & further reading

USCIS: Constitution Day & Citizenship Day; USCIS stakeholder messages about the observance. (USCIS)

Congressional Research Service (2025): Constitution Day and Citizenship Day: Fact Sheet. (gov)

NARA: Naturalization records overview; clues in census records; certificate/C‑File history. (NARA)

USCIS Genealogy Program: Requesting records; searching the index. (USCIS)

Alien Registration (AR‑2) & A‑Files: USCIS and NARA guidance. (USCIS)

Legal context: Racial restrictions lifted by the Immigration and Nationality Act of 1952. (Office of the Historian)

Married women & citizenship: NARA Prologue on women’s naturalization/repatriation. (National Archives)

Ancestry® naturalization collections: Browse by state and federal holdings. (Ancestry)

Bottom line: National Citizenship Day is more than a date on the calendar—it’s your once‑a‑year invitation to trace how your family joined the American story. Open Ancestry, check those census clues, and follow the paper trail. Whether you land on a glowing petition, a revealing AR‑2, or the realization that citizenship was derived (or never sought), you’ll come away with new insight—and a deeper connection to your immigrant ancestors.

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Author’s Note: I want to be transparent that this article – National Citizenship Day (Sept 17): A Perfect Prompt to Research Your Immigrant Ancestors’ Path to U.S. Citizenship – was created in part with the help of an artificial intelligence (AI) language model – ChatGPT 5o PRO with Deep Reasoning. The AI assisted in generating an early draft of the article, but every paragraph was subsequently reviewed, edited, and refined by me. The final content is the result of extensive human curation and creativity. I am proud to present this work and assure readers that while AI was a tool in the process, the story, style, and substance have been carefully shaped by the author.